Apparatus for cutting thin sections



Aug. 4, 1953 P. G. ROOFE ET AL APPARATUS FOR CUTTING THIN SECTIONS FiledAug. 253 1949 mm m ATT'Y Patented Aug. 4, 1953 APPARATUS FOR CUTTINGTHIN SECTIONS Paul G. Roofe and Frank E. Hoecker, Lawrence, Kans.

Application August 23, 1949, Serial No. 111,921

Claims. 1

This invention relates in general to the cutting of thin sections ofteeth, bones, rocks and other hard objects and is more particularlydescribed in the sectioning of bones for photomicrographic andautoradiographic purposes, although it may have a more general usewherever applicable.

The recent development of interest in the absorption, distribution andbiological effects of radioactive substances absorbed into the bodies ofexperimental animals has led to the development of methods of studyingvarious tissues by autoradiographic methods. A really satisfactorymethod of preparing sections of bone has been lacking for studies whichprecluded decalcification.

One method which involved rather elaborate treatment of the bone beforeand during the process ofsectioning, included, among otherdisadvantages, the necessity of mounting the bone to be sectioned incelloidin, a process requiring at least ten days delay and someuncertainty as to the proper hardness of the celloidin block. One of theserious objections to this method is the difficulty and time consumingprocess of grinding nicks out of the microtome knife after a fewsections have been out.

The distribution and possible effects of radium deposited in the bonesof test animals have emphasized the necessity of a rapid method ofsectioning the bones of animals which have been injected with radiumchloride. The present invention has the following advantages, objects,and virtues:

No treatment of the bone before sectioning is required;

The method is rapid, as thirty serial sections of a rat tibia can bemade in an hour;

The sections are sufficiently thin (of the order of microns) formicroscopic and photomicrographic study of the cellular structure of thebone; and

No subsequent treatment of the bone section is required, the section issimply removed from a section retainer of the cutter and mounteddirectly upon a slide with sumcient adhesive in insure attachment.

A further object of the invention is to provide an apparatus which iseasily and rapidly operated, it is readily adjustable for difierentarticles and different sections, and improved means are provided forholding the bones and the sections as they are removed.

Other objects of the invention will appear in the specification and willbe apparent from the accompanying drawing, in which The figure is apart-sectional view of an apparatus for holding an article, such as abone, without damaging it and for cutting and retaining each thinsection as it is separated from the bone.

In carrying out this invention a section holding carriage 8 is movablerelatively to a motor driven saw [0 for cutting a thin section I2 from abone I4 held by the carriage, and a section retainer blade It holds thethin section [2 during the time and after it is cut off.

Referring now more particularly to the drawings, the carriage 8 is shownin the form of a channel mounted for relative raising and loweringmovement upon a support l8 by means of a post 20 connected to the bottomof the carriage and having a rack 22 in the post and a pinion 24engaging the rack and rotatably mounted in the support It. If desired afeeding pawl 26 movably mounted in the support l8 engages the pinion 24to rotate it in a step-by-step movement for raising or advancing thebone I4 the thickness of the cut desired.

The carriage is also movable reciprocably with the support relatively tothe saw [0 in any suitable manner, as represented by a rack 30 on thesupport l8 and a pinion 32 meshing therewith and movable in oppositedirections. As thus represented the saw is fixed in location while thecarriage is shifted, but the same result is obtained if the the carriageis stationary and the motor saw is moved horizontally and verticallywith respect to the carriage.

In the carriage channel are blocks 34 and 36, each with a leather piece38 secured to one face and a soft rubber piece 40 secured to the outersurface of the leather piece. These two blocks are placed oppositelywith the leather and rubber pieces adjacent and the bone [4 to besectioned between the rubber faces. The blocks are pressed together,binding the bone tightly in place between them as cushioned by theleather and rubber pieces, by a metal spacer 42 engaged on one side by aclamping screw 44 extending through one side of the carriage channelmember and having a head 46 at the outer end for adjusting the screw.

In one of the blocks 36 and extending upwardly therefrom is a supportingrod 50 upon which a collar 5| is slidably adjustable by means of a screw52. Extending from the collar is the section retainer blade l6comprising a spring strip preferably of metal, bent outwardly anddownwardly therefrom. The outer end of the strip is attached to theupper end of the bone [4 before it is severed by a suitable adhesive 56.This spring strip supports the upper section as it is being severed andretains it after it has been cut ofi by the saw H1. The section thus cuton is removed from the spring strip and mounted on a microscope slide bya thin clear adhesive, and the photomicrogram is made therefrom.

After one section is cut off, the carriage is withdrawn if necessary,raised the thickness of the cut section desired, the end of the springstrip [6 is adhesively secured to the cut and projecting end of thebone, and the cutting operation is repeated. It ,may b necessary toadjust the bone 14 in the holder which comprises the clamping blocks 34and 36 with their interposed yielding and resilient pieces. These piecesmay be separate from the blocks for independently positioning them, ifdesired.

Although this apparatus has been described in detail as applied to thecutting and mounting of a thin bone section, it should be regarded asanexample or illustration and not as a limitation or restriction, asvarious changes may be made in the construction and application of theparts for cutting thin sections of other mavterials without departingfrom the spirit and scope of the invention.

The invention described herein may be manufactured and used by or forthe Government of the United States of America for governmental purposeswithout the payment of any royalties thereon or therefor.

We claim:

1. The combination with a holder for an article and a cutter movablewith respect to the holder and the article for severing a thin sectionfrom one end of the article, of a retainer for the thin sectioncomprising an adhesive to engage the said one end of the articl beforethe severing operation, the retainer comprising a spring for carryingthe adhesive yielding urged against the said one end of the sectionbeing flexible to enabl the retainer and severed sec- ..tion adheringthereto to be moved away from the article after the severing operation.

2. The combination with a holder for an article and a cutter movablewith respect to the holder andthe article for severing a thin sectionfrom one end of the article, of a resilient retainer for the thinsectionhaving anadhesive at one end to engage th said one end of thearticle before the severing operation and secured 4 at its other end infixed relation with respect to the holder so as to cause the adhesiveand said one end of the retainer to be yieldingly urged against the saidone end of the article, whereby the said one end of the retainer alongthe severed section adhering thereto may be moved away from the articlfor removal of the section from the retainer.

3. They apparatus specified in claim 2, the retainerbeing aflexiblespring strip.

4. The combination with a holder for a bone and a cutter movable withrespect to the holder for severing .a thin section from one end of thebone, of a retainer 'for the thin section of bone comprising. aresilient strip having an adhesive at one end to engage the said one endof the bone before the severing operation, and means for adjustablysecuring the other end of the a holder movable relative to said cutterfor clamping the article to be sliced atv only one end thereof to allowthe free end thereof to extend into the path of said cutter, a resilientstrip supported by the holder and curved to, yieldingly press againsttheouter end of said article. and an adhesive carried by the strip forengagingand for retaining the portion sliced in its position relative tothe rest of said article both during and subsequent to the slicingoperation.

PAUL G. ROOFE.

FRANK E. HQECKER.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,013,897 7 Reilly et a1 Jan. 9, 1912 1,923,854 Van Hoorn Aug.22; 1933 1,929,543 Van Hoorn Oct. 10, 1933 2,086,159 Wood July 13, 1937FOREIGN PATENTS Number Country Date 402,888 'Germany Sept. 19, 1924

